LAUSR

BACKGROUND The air-induction nozzle greatly reduces the drift potential by increasing spray droplet size compared with the standard flat-fan nozzle. The present study aims to reveal the mechanism of the generation of large droplets for the air-induction nozzle from the aspect of bubble evolution in the spray sheet. RESULTS The breakup of bubbles leads directly to the formation of perforations as large bubbles reach both sides of the spray sheet. The surface disturbance induced by bubble breakup modulates the sheet thickness, which indirectly cause the generation of perforations. Compared with spray pressure, the nozzle configuration has a more significant effect on both volumetric flow rate of intake air and the thickness of the spray sheet. As the nozzle is changed from ID-120-01 to ID-120-05, the volumetric flow rate of intake air increases by 801.30% at a spray pressure of 0.3 MPa, while the thickness of the spray sheet increases by 412.50% at the radial distance of 10 mm. CONCLUSION The breakup of bubbles serves as the main reason of the generation of perforations with the air-induction nozzle, which lead to early breakup of the spray sheet and the production of large spray droplets. The breakup of bubbles can be effectively controlled by modifying the nozzle configuration.